Researchers warn that only DTP is on track to reach 90% global coverage by 2030, while measles and pneumococcal vaccines lag behind significantly.

More than 14 million children around the world have not received a single dose of any vaccine, according to new data from the World Health Organization and UNICEF.

U.N. health officials have estimated that more than 14 million children did not receive a single vaccine last year.

WHO attributes declining immunisation rates to limited access to inoculation services, disrupted supply chains and conflict.